I also use Goo Gone. I have wiped it on and off with a rag, and I've used it in my old Centerline track cleaning car and let it clean all my track, and all my wheels at the same time. That is the way to do it! I wipe the track that I can reach dry but don't worry about the rest. The Goo Gone will dry overnight.
The electrical conductivity improvement between the track and the engines and cars is remarkable! Everyone that uses it after I tell them about it comes back and thanks me over and over again. The trains run smoother, passenger car lights are brighter, and old postwar trains can be run slower than ever before.
The past president of Lionel highly recommends (personally and professionally) using Goo Gone. He even posted about using it here on OGR. After I first read his thread and decided to try it: When I got out my Centerline track cleaning car that I bought in 1984 guess what their enclosed paperwork suggests using with it . . . Goo Gone.
Goo Gone is citric based. There are a lot of "I heard" Goo Gone will hurt rubber traction tires. But noone has ever posted that they personally know it does. That is an internet myth. It does not hurt rubber tires.